About 3 months of saved sessions have disappeared

[ReddishPython]

Short description

Upon opening firefox today,I noticed that there were some tabs missing. I opened tab session manager and there are no saved sessions listed. It looks like the addon restored a session from january.
I had setup the addon to save the session both periodically and when firefox closes, but the saved sessions cannot be found anywhere.
Is there a way to recover them?

Additionaly, the "export" button in the settings appears to do nothing as it doesn't generate any file or download prompt

Platform information

• Platform (OS): Windows
• Version of browser: Firefox 124.0.1
• Version of Tab Session Manager: 6.12.2

Additional context

[0HMyC]

Ran into this problem as well, noticed all but one of my sessions just randomly disappeared completely; Windows, Firefox 118.0.1 w/ 6.12.2 of Tab Session Manager.

I decided to try seeing if I could recover anything from the extensions data folder (in my case at (AppData\Roaming\Mozilla\Firefox\Profiles\*.default\storage\default\moz-extension+++b36fdf43-6b71-4726-8b6a-bb5d238fcd43) and I did notice a bunch of files named as 6-digit numbers in the idb\1782160246ssensosi.files directory which when opened in a hex editor would appear to be the files that the extension uses to store your sessions (which can be identified by the urls/browser tab text being clearly stored in these files), which tells me that this bug might not be deleting anything but for some reason the extension just... stops being able to see your older sessions somehow???

With that being said I've got no clue how I would be able to coerce the extension into properly reading these files again; I'm at least lucky enough to have had the session backup feature enabled which does mean all my sessions saved from up to the start of the month can be restored thankfully, but that obviously won't help much for anyone who didn't already have that feature enabled :/

Edit: Experimented with trying to re-import one of the session backups I had, and not only did it not appear in the extension, but I also tested trying to save a new session (which did work) but then once I reopened the extension window again the new session I saved was the only one being shown with the previous one now no longer appearing; seems like the issue is that somehow only one session is being shown at a time (which whatever that session is probably being random in some way?) Very unusual and frusturating to be sure

[ReddishPython]

I did some digging and I found those files too, the last modified date shows a gap between January 9 and March 27 (the day I discovered something went wrong).
What's strange is that I periodically do a manual save of my sessions and I'm sure I did one in mid February for sure. I unfortunately don't export my sessions to a file that often because so far I never felt the need to, the extension has worked flawlessly for years.

Seems like something ate about 3 months' worth of files and I don't have much hope of recovering them.

In the meantime I'm tediously combing through my history (which is completely fine) and trying to recover what I can.

[ReddishPython]

Issue seems fixed after updating to 7.0.1, after saving a new session, old ones reappeared in the drop down menu

[therealblaznik]

Having this exact same issue. Just like described above, every time I open the manager it only shows 1 saved session, the last one. The weird thing is I'm already on 7.0.1, so can't rely on that fix which seemed to work for you. I'm thinking of trying to reinstall the add-on, but worried that that might cause more harm. I found the folder with the saved sessions and made a backup just in case. Can those files be opened somehow, or can the tabs from a session be extracted? Any ideas on next steps?